Poetry has been pronounced dead time and time again, but literary doomsayers may want to check Instagram before nailing the coffin shut.

It is there that Miami native Robert Macias, who uses the pseudonym R.M. Drake, has forged a space in the mainstream for the out-of-favor art form. And his reach is considerable — Macias has amassed more than one million followers on his poetry account @rmdrk since joining Instagram in November 2012...